Data transmission speed and quality are important for data communication systems and networks. Data may be transmitted according to various data transmission protocols. Multi-level signal modulation, such as pulse-amplitude modulation (PAM), is used for enhancing data rate in bandwidth limited data communication channels. An important parameter of a transmitter is the linearity of the output signal generated by the transmitter. Based on the linearity of the output signal, it may be determined that the deviation of each signal level in the output signal from the corresponding expected value is small, and therefore that an expected value of a particular signal level may be derived from positions of other signal levels. The linearity of the output signal may affect the performance (e.g., the bit error rate of received data) of data transmission.
Accordingly, it would be desirable and useful to provide an improved method and system for generating a modulated signal in a transmitter.